A aqua regia boiling water bath digestion atomic fluorescence spectrophotometry method was established for the determination of bismuth in soil and sediment. The instrument parameters, current carrying capacity, and reducing agent concentration were optimized, and the advantages and disadvantages of water bath digestion, microwave digestion, and electric heating plate digestion in treating bismuth in soil/sediment were compared. Experiments have shown that the optimal digestion method is water bath digestion, which is simple, convenient, accurate, and reliable. The detection limit of the method for dissolving soil or sediment samples using aqua regia boiling water bath is 0.01 mg/kg (with a sample size of 0.5000 g and a constant volume of 50 mL), and the detection limit is 0.04 mg/kg. This method determines soil standard samples, and the measured values are within the standard range, with a relative error of -4.4% to -20%. This method is used to determine the relative standard deviations of actual soil and sediment samples, which are 2.5% -3.4% and 3.1% -3.4%, respectively. The spiked recovery rates are 97.6% -102% and 99.5% -104%, respectively.

Recommended instruments:Jitian second-hand atomic fluorescence spectrophotometer AFS-930